Studies on properties and ligand interactions of cluster II and IV of low-density lipoprotein receptor-related protein 1 (LRP1) expressed in Escherichia coli

Abstract

Low-density lipoprotein receptor-associated protein 1 (LRP1) is an endocytic receptor involved in various types of biological processes with its ligand-binding abilities. The interactions of LRP1 mainly occur on the second and fourth clusters, which consist of several complement-type repeat (CR) domains. Therefore, I expressed clusters II and IV of LRP1 from Escherichia coli, an effective host for expressing recombinant proteins with its high yield compared with its cost and culture volume, and studied its properties and interactions through diverse methods, including analytical size-exclusion chromatography (ASEC), analytical ultracentrifugation (AUC), fluorescence emission spectroscopy, circular dichroism (CD) spectroscopy, and surface plasmon resonance (SPR). As a result, I observed their oligomerization, strong Ca2+ dependence for structural stability, and low affinity with their ligands. However, these results need to be proved with other E. coli strains, vectors, and conditions for induction.